1、_ SAE Technical Standards Board Rules provide that: “This report is published by SAE to advance the state of technical and engineering sciences. The use of this report is entirely voluntary, and its applicability and suitability for any particular use, including any patent infringement arising there
2、from, is the sole responsibility of the user.” SAE reviews each technical report at least every five years at which time it may be revised, reaffirmed, stabilized, or cancelled. SAE invites your written comments and suggestions. Copyright 2016 SAE International All rights reserved. No part of this p
3、ublication may be reproduced, stored in a retrieval system or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of SAE. TO PLACE A DOCUMENT ORDER: Tel: 877-606-7323 (inside USA and Canada) Tel: +1 724-776-497
4、0 (outside USA) Fax: 724-776-0790 Email: CustomerServicesae.org SAE WEB ADDRESS: http:/www.sae.org SAE values your input. To provide feedback on this Technical Report, please visit http:/www.sae.org/technical/standards/AS7454B AEROSPACE STANDARD AS7454 REV. B Issued 1991-02 Reaffirmed 2006-05 Revise
5、d 2016-04 Superseding AS7454A Bolts and Screws, Steel, Low Alloy, Heat Resistant 135,000 psi Tensile Strength, Normalized and Tempered, Roll Threaded FSC 5306 RATIONALE Revise and update sampling and inspection requirements, clarify fillet rolling requirements, and general editorial update. 1. SCOPE
6、 1.1 Type This procurement specification covers aircraft quality bolts and screws made from a low alloy, heat resistant steel of the type identified under the Unified Numbering System as UNS K14675. AS7454 135,000 psi ultimate tensile strength at room temperature. AS7454-1 135,000 psi ultimate tensi
7、le strength at room temperature, nickel-cadmium plated. 1.2 Application Primarily for aerospace propulsion system applications where good strength at temperatures up to approximately 900 F is required and the part is protected against corrosion. 1.3 Safety - Hazardous Materials While the materials,
8、methods, applications, and processes described or referenced in this specification may involve the use of hazardous materials, this specification does not address the hazards which may be involved in such use. It is the sole responsibility of the user to ensure familiarity with the safe and proper u
9、se of any hazardous materials and to take necessary precautionary measures to ensure the health and safety of all personnel involved. SAE INTERNATIONAL AS7454B Page 2 of 20 2. REFERENCES 2.1 Applicable Documents The following publications form a part of this document to the extent specified herein.
10、The latest issue of SAE publications shall apply. The applicable issue of other publications shall be the issue in effect on the date of the purchase order. In the event of conflict between the text of this document and references cited herein, the text of this document takes precedence. Nothing in
11、this document, however, supersedes applicable laws and regulations unless a specific exemption has been obtained. 2.1.1 SAE Publications Available from SAE International, 400 Commonwealth Drive, Warrendale, PA 15096-0001, Tel: 877-606-7323 (inside USA and Canada) or +1 724-776-4970 (outside USA), ww
12、w.sae.org. AMS2416 Plating, Nickel-Cadmium, Diffused AMS2750 Pyrometry AMS6304 Low-Alloy Steel, Heat Resistant, Bars, Forgings, and Tubing 0.95Cr - 0.55Mo - 0.30V (0.40 - 0.50C) AS1132 Bolts, Screws and Nuts - External Wrenching UNJ Thread, Inch - Design Standard AS3062 Bolts, Screws, and Studs, Scr
13、ew Thread Requirements AS3063 Bolts, Screws, and Studs, Geometric Control Requirements AS8879 Screw Threads - UNJ Profile, Inch Controlled Radius Root with Increased Minor Diameter 2.1.2 U.S. Government Publications Copies of these documents are available online at http:/quicksearch.dla.mil. MIL-STD
14、-2073-1 Military Packaging, Standard Practice for 2.1.3 ASTM Publications Available from ASTM International, 100 Barr Harbor Drive, P.O. Box C700, West Conshohocken, PA 19428-2959, Tel: 610-832-9585, www.astm.org. ASTM E140 Standard Hardness Tables for Metals ASTM E1444/E1444M Magnetic Particle Exam
15、ination ASTM E8/E8M Tension Testing of Metallic Materials 2.1.4 ASME Publications Available from ASME, P.O. Box 2900, 22 Law Drive, Fairfield, NJ 07007-2900, Tel: 800-843-2763 (U.S./Canada), 001-800-843-2763 (Mexico), 973-882-1170 (outside North America), www.asme.org. ASME B46.1 Surface Texture (Su
16、rface Roughness, Waviness, and Lay) SAE INTERNATIONAL AS7454B Page 3 of 20 2.1.5 AIA Publications Available from Aerospace Industries Association, 1000 Wilson Boulevard, Suite 1700, Arlington, VA 22209-3928, Tel: 703-358-1000, www.aia-aerospace.org. NASM1312-6 Fastener Test Methods, Method 6, Hardne
17、ss NASM1312-8 Fastener Test Methods, Method 8, Tensile Testing NASM1312-12 Fastener Test Methods, Method 12, Plating Thickness 2.2 Definitions BURR: A rough edge or ridge left on the metal due to cutting, grinding, piercing, or blanking operation. COLD ROLLING: Forming material below the recrystalli
18、zation temperature. CRACK: Rupture in the material which may extend in any direction and which may be intercrystalline or transcrystalline in character. DEFECT: Any nonconformance of the unit or the product with specified requirements. DEFECTIVE: A unit of the product which contains one or more defe
19、cts. DISCONTINUITY: An interruption in the normal physical structure or configuration of a part; such as a lap, seam, inclusion, crack, machining tear, or stringer. HEAT PATTERN: A discernible difference in etched appearance between the head and the shank caused by forming of the head. INCLUSION: No
20、nmetallic particles originating from the material making process. They may exist as discrete particles or strings of particles extending longitudinally. LAP: Surface imperfection caused by folding over metal fins or sharp corners and then rolling or forging them into the surface. The allowable lap d
21、epth shall not exceed the limit specified herein. The minimum condition that shall be rated as a lap is a fold having its length equal to or greater than three times its width with a depth of 0.0005 inch when viewed at 200X magnification. MACHINING TEAR: A pattern of short jagged individual cracks,
22、generally at right angles to the direction of machining, frequently the result of improperly set cutting tools, or dull cutting tools. PRODUCTION INSPECTION LOT: Shall be all finished parts of the same part number, made from a single heat of alloy, heat treated at the same time to the same specified
23、 condition, produced as one continuous run, and submitted for manufacturers inspection at the same time. SEAM: Longitudinal surface imperfection in the form of an unwelded, open fold in the material. STRINGER: A solid nonmetallic impurity in the metal bar, often the result of an inclusion that has b
24、een extended during the rolling process. TIGHT BURR: A burr closely compacted and binding in the periphery of a part without loose ends and is within the dimensional limits of the part. SAE INTERNATIONAL AS7454B Page 4 of 20 2.3 Unit Symbols A - ampere F - degree Fahrenheit % - percent (1% = 1/100)
25、lbf - pounds force psi - pounds force per square inch sp gr - specific gravity 3. TECHNICAL REQUIREMENTS 3.1 Material Shall be AMS6304 steel, unless otherwise specified on the part drawing. 3.2 Design Finished (completely manufactured) parts shall conform to the following requirements: 3.2.1 Dimensi
26、ons The dimensions of finished parts, after all processing, including plating, shall conform to the part drawing. Dimensions apply after plating but before coating with solid film lubricants. 3.2.2 Surface Texture Surface texture of finished parts, prior to plating or coating, shall conform to the r
27、equirements as specified on the part drawing, determined in accordance with ASME B46.1. 3.2.3 Threads Screw thread UNJ profile and dimensions shall be in accordance with AS8879, unless otherwise specified on the part drawing. 3.2.3.1 Incomplete Threads Incomplete threads are permissible at the chamf
28、ered end and the juncture of the unthreaded portion of the shank or adjacent to the head as specified in AS3062. 3.2.3.2 Chamfer The entering end of the thread shall be chamfered as specified on the part drawing. 3.2.4 Geometric Tolerances Part features shall be within the geometric tolerances speci
29、fied on the part drawing and, where applicable, controlled in accordance with AS3063. 3.3 Fabrication 3.3.1 Blanks Heads shall be formed by hot forging, cold forging, or machining. Lightening holes may be produced by any suitable method. Wrenching recesses may be forged or machined. Flash or chip cl
30、earance in machined recesses shall not cause recess dimensions to exceed the specified limits. SAE INTERNATIONAL AS7454B Page 5 of 20 3.3.2 Heat Treatment Headed and machined blanks shall, before finishing the shank and the bearing surface of the head, cold working the head-to-shank fillet radius wh
31、en specified, and rolling the threads, be heat treated as follows: 3.3.2.1 Heating Equipment Furnaces may be any type ensuring uniform temperature throughout the parts being heated and shall be equipped with, and operated by, automatic controllers and data recorders conforming to AMS2750. The heatin
32、g medium or atmosphere shall cause neither surface hardening nor decarburization other than that permitted by 3.7.2.2 and 3.7.2.3. 3.3.2.2 Normalizing Blanks of AMS6304 shall be uniformly heated to 1750 F 25 F, held at heat for 60 to 90 minutes, and cooled in still air or in a cooling chamber of the
33、 furnace. 3.3.2.3 Tempering Normalized blanks of AMS6304 shall be tempered by heating uniformly to the temperature necessary to produce the specified hardness and microstructure but not lower than 1100 F, holding at heat for not less than 6 hours, and cooling in air. 3.3.2.4 For steels other than AM
34、S6304, heat treatment shall be as agreed upon by purchaser and manufacture. 3.3.3 Oxide and Decarburization Removal Surface oxide, oxide penetration, and decarburization except as permitted in 3.7.2.3, resulting from prior heat treatment, shall be removed from the full body diameter and bearing surf
35、ace of the head of the heat treated blanks prior to cold working the under head fillet radius when specified and rolling the threads. The oxide removal process shall produce no intergranular attack or corrosion of the blanks. The metal removed from the bearing surface of the head and the full body d
36、iameter of the shank shall be as little as practicable to obtain a clean, smooth surface and, in no case, shall be so great as to produce more cutting of flow lines in the head-to-shank junction of forged headed parts than shown in Figure 1B. 3.3.4 Cold Working of Fillet Radius After removal of oxid
37、e and decarburization as in 3.3.3, the head-to- shank fillet radius of headed parts having the radius complete throughout the circumference of the part shall be cold rolled. The cold rolling shall be sufficient to remove all visual evidence of grinding or tool marks. Distortion due to cold working s
38、hall conform to Figure 2, unless otherwise specified on the part drawing. It shall not raise metal more than 0.002 inch above the contour at “A“ or depress metal more than 0.002 inch below the contour at “B“ as shown in Figure 2; distorted areas shall not extend beyond “C“ as shown in Figure 2. In c
39、onfigurations having an undercut associated with the fillet radius, the cold working will be required only for 90 degrees of fillet arc, starting at the point of tangency of the fillet radius and the bearing surface of the head. In addition to cold working the head-to-shank fillet radius, shouldered
40、 bolts having an unthreaded shank diameter larger than the thread major diameter and having an undercut associated with a fillet between the threaded shank and the shoulder of the unthreaded shank, the cold working will be required only for 90 degrees of fillet arc, starting at the point of tangency
41、 of the fillet radius and the shouldered surface of the unthreaded shank. For parts with compound fillet radii between head and shank, cold work only the radius that blends with the head. 3.3.5 Thread Rolling Threads shall be formed on the heat treated and finished blanks by a single rolling process
42、 after removal of oxide and decarburization as in 3.3.3. 3.4 Product Marking Each part shall be identification marked as specified by the part drawing. The markings may be formed by forging or stamping, raised or depressed not more than 0.010 inch maximum, with rounded root form on depressed charact
43、ers. SAE INTERNATIONAL AS7454B Page 6 of 20 3.5 Plating Where AS7454 is specified, any protective treatment shall be as specified on the part drawing. Where AS7454-1 is specified, parts shall be nickel-cadmium plated in accordance with AMS2416. 3.6 Mechanical Properties Parts shall conform to the re
44、quirements of 3.6.1 and 3.6.2. Threaded members of gripping fixtures for tensile test shall be of sufficient size and strength to develop the full strength of the part without stripping the thread. The loaded portion of the shank shall have two to three full turns from the thread runout exposed betw
45、een the loading fixtures during the tensile test. Finished parts shall be tested in accordance with the following applicable test methods: a. Hardness: MIL-STD-1312-6 in accordance with NASM1312-6. b. Room Temperature Ultimate Tensile Strength: MIL-STD-1312-8 in accordance with NASM1312-8. 3.6.1 Ult
46、imate Tensile Strength at Room Temperature 3.6.1.1 Finished Parts Parts having hardness as in 3.6.2 shall have an ultimate tensile load not lower than that specified in Table 2 and shall be tested to failure, first measuring and recording the maximum tensile load achieved. If the size or shape of th
47、e part is such that failure would occur outside the threaded section but the part can be tested satisfactorily, such as parts having a shank diameter equal to or less than the thread root diameter or having an undercut, parts shall conform to only the tensile requirements of 3.6.1.2; for such parts,
48、 the diameter of the area on which stress is based shall be the actual measured minimum diameter of the part. Tension fasteners with either standard double hexagon or hexagon-type heads having a minimum metal condition in the head equal to the design parameters specified in AS1132 shall not fracture
49、 in the head-to-shank fillet radius except when this radius is associated with an undercut or with a shank diameter less than the minimum pitch diameter of the thread. 3.6.1.2 Machined Test Specimens If the size or shape of the part is such that a tensile test cannot be made on the part, tensile tests shall be conducted in accordance with ASTM E8/E8M on specimens prepared as in 4.5. Such specimens shall meet the following
